Job Description
Senior Full Stack Engineer – Kotlin / Spring Boot / React
Sydney | Hybrid | 6-Month Day Rate Contract + Likely Extension
We're partnering with a major Australian enterprise going through significant technology transformation, with a number of
greenfield initiatives
on the roadmap.
We're looking for a strong
backend-leaning Full Stack Engineer
who enjoys solving complex problems, owning outcomes and working across the stack when needed.
The opportunity
You'll work within a modern product engineering environment, building and evolving scalable applications while contributing to new greenfield development.
The backend is centred around
Kotlin and Spring Boot
, but this isn't a purely backend role.
You'll need enough frontend capability to comfortably work across modern JavaScript applications, with
TypeScript and React
particularly relevant.
There's also a strong focus on how engineers are
harnessing AI tooling to improve the way they build software
.
We're keen to meet developers already using tools such as Claude Code, Cursor,



Copilot or coding agents to accelerate development, testing, debugging and delivery.
What we're looking for
Strong
Kotlin / Java and Spring Boot
engineering experience
Genuine
full stack capability
, with a backend bias
Exposure to
JavaScript, TypeScript and/or React
Experience building
APIs, microservices and distributed applications
Good exposure to modern
AWS or GCP
cloud environments
Engineers actively incorporating
AI tooling into their development workflows
Strong problem-solving skills and the ability to take ownership from idea through to production
Comfortable working within modern CI/CD and product engineering environments
Initial 6-month day rate contract with a strong likelihood of extension.
If you're a hands-on engineer who enjoys difficult technical problems, up-to-date technology and the opportunity to contribute to genuine greenfield development, I'd be keen to hear from you.

📌 Staff Engineer (Spring Boot) (Kotlin) (Gcp)
🏢 The Onset
📍 New South Wales